U.S. patent application number 11/322292 was filed with the patent office on 2006-08-03 for data loss control in a push to communicate network.
This patent application is currently assigned to LG Electronics Inc.. Invention is credited to Guk-Chan Lim.
Application Number | 20060171338 11/322292 |
Document ID | / |
Family ID | 36051546 |
Filed Date | 2006-08-03 |
United States Patent
Application |
20060171338 |
Kind Code |
A1 |
Lim; Guk-Chan |
August 3, 2006 |
Data loss control in a push to communicate network
Abstract
An audio data retransmission method in a push to communicate
(PTx) terminal for transmitting data by pressing a PTx key is
provided. The method comprises transmitting data using a
transmitting PTx terminal; storing the data in a buffer; and
retransmitting the data when receiver requests retransmission due
to a loss in communications.
Inventors: |
Lim; Guk-Chan; (Gyeonggi-Do,
KR) |
Correspondence
Address: |
LEE, HONG, DEGERMAN, KANG & SCHMADEKA
14th Floor
801 S. Figueroa Street
Los Angeles
CA
90017
US
|
Assignee: |
LG Electronics Inc.
|
Family ID: |
36051546 |
Appl. No.: |
11/322292 |
Filed: |
December 29, 2005 |
Current U.S.
Class: |
370/278 ;
370/412; 714/748 |
Current CPC
Class: |
H04W 4/10 20130101; H04L
65/1016 20130101; H04L 65/4061 20130101; H04W 76/45 20180201 |
Class at
Publication: |
370/278 ;
370/412; 714/748 |
International
Class: |
H04B 7/005 20060101
H04B007/005; H04L 12/56 20060101 H04L012/56 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 29, 2004 |
KR |
10-2004-0115558 |
Claims
1. A data retransmission method in a push to communicate (PTx)
communications network for transmitting data from a transmitting
PTx terminal to a receiving PTx terminal, the method comprising:
transmitting first data from a transmitting PTx terminal to a
receiving PTx terminal; storing the first data; and retransmitting
the first data in response to the receiving PTx terminal requesting
retransmission of the first data.
2. The method of claim 1, wherein the first data is stored in a
buffer.
3. The method of claim 2, wherein the buffer is implemented as at
least one of an internal memory and an external memory in the
transmitting PTx terminal.
4. The method of claim 1, further comprising outputting the first
data through a speaker in the retransmitting process.
5. The method of claim 1, wherein the first data is deleted when a
PTx key of the transmitting PTx terminal is pressed to transmit
second data.
6. The method of claim 1, wherein a PTx key is implemented on the
transmitting PTx terminal, such that interacting with the PTx key
results in transmission of the first data.
7. An audio data retransmission method in a push to communicate
(PTx) terminal for transmitting audio data, the method comprising:
setting an automatic audio retransmission function; storing audio
data, to be transmitted to a receiver PTx terminal, in a buffer;
and retransmitting the audio data stored in the buffer, in response
to the receiver PTx terminal requesting retransmission of the audio
data.
8. The method of claim 7, wherein the stored audio data is deleted
after the audio data is successfully delivered to the receiver PTx
terminal.
9. The method of claim 7, wherein the PTx terminal comprises a
designated PTx key for setting the automatic audio retransmission
function.
10. The method of claim 7, wherein the PTx terminal comprises a key
on a keypad of the PTx terminal for activating the automatic audio
retransmission function.
11. A mobile terminal apparatus that supports a push to communicate
(PTx) function, the apparatus comprising: a radio frequency unit
adapted to communicate radio communication signals; a codec adapted
to process audio inputs provided by a user via a PTx function; a
memory adapted to store the processed audio inputs; and a
microprocessor unit adapted to control said codec to forward the
processed audio inputs to said memory for storage after the
processed audio inputs are transmitted to another user via said
radio frequency unit, the microprocessor unit further adapted to
control said radio frequency unit, said codec, and said memory to
re-transmit the processed audio inputs stored in said memory, if
said another user requests re-transmission of the processed audio
inputs due to a loss in transmission.
12. The apparatus of claim 11, wherein the processed audio inputs
are temporarily stored in said memory until the user provides
subsequent audio inputs via the PTx function.
13. The apparatus of claim 12, wherein the processed audio inputs
temporarily stored in said memory are deleted therefrom if said
another user does not request re-transmission by the time the user
provides the subsequent audio inputs via the PTx function.
14. The apparatus of claim 11, wherein the mobile terminal is a PTx
terminal.
15. A communication network configured for supporting a push to
communicate (PTx) communication protocol, the communication network
comprising a plurality of base stations in communication with a
plurality of PTx terminals, wherein a transmitting PTx terminal
requests a talk burst grant from a PTx server for transmitting
audio data to a receiving PTx terminal, wherein the transmitting
PTx terminal stores the audio data in a storage medium when the
request for talk burst grant is submitted, so that if the receiving
PTx terminal fails to receive the audio data, the stored audio data
is retransmitted.
16. A data communication protocol for a push to communicate (PTx)
mobile communications network comprising: detecting a floor grant
for data communication between a transmitting PTx terminal and a
receiving PTx terminal; determining whether a failure has occurred
in transmitting first data to the receiving PTx terminal; and
notifying the transmitting PTx terminal of failure in data
transmission, wherein the transmitting PTx terminal retransmits the
first data in response to receiving a failure notice, and wherein
the first data is stored in a storage medium of the transmitting
PTx terminal.
17. The data communication protocol of claim 16, wherein the
failure in transmitting the first data is determined, when a
threshold time has lapsed from time of the floor grant.
18. The data communication protocol of claim 16, wherein the
failure in transmitting the first data is determined, when the
transmitting PTx terminal does not receive an acknowledgement of
receipt from the receiving PTx terminal.
19. The data communication protocol of claim 16, wherein the
transmitting PTx terminal automatically retransmits the first
data.
20. The data communication protocol of claim 16, wherein the
transmitting PTx terminal retransmits the first data in response to
user interaction with the transmitting PTx terminal.
21. A push to communicate (PTx) terminal comprising: a transmitting
unit for requesting a floor grant for data communication between a
transmitting PTx terminal and a receiving PTx terminal; memory for
storing the first data in a storage medium of the transmitting PTx
terminal; and a processing unit for determining a communication
failure, if a failure occurs in transmitting first data to the
receiving PTx terminal, wherein in response to determining a
communication failure, the transmitting PTx terminal retransmits
the first data.
22. The PTx terminal of claim 21, wherein the failure in
transmitting the first data is determined, when a threshold time
has lapsed from time of the floor grant.
23. The PTx terminal of claim 21, wherein the failure in
transmitting the first data is determined, when the transmitting
PTx terminal does not receive an acknowledgement of receipt from
the receiving PTx terminal.
24. The PTx terminal of claim 21, wherein the transmitting PTx
terminal automatically retransmits the first data.
25. The PTx terminal of claim 21, wherein the transmitting PTx
terminal retransmits the first data in response to user interaction
with the transmitting PTx terminal.
26. The PTx terminal of claim 21, wherein the PTx terminal is the
transmitting PTx terminal.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Pursuant to 35 U.S.C. .sctn. 119(a), this application claims
the benefit of earlier filing date and right of priority to Korean
Patent Application No. 115558/2004, filed on Dec. 29, 2004, the
content of which is hereby incorporated by reference herein in its
entirety.
FIELD OF INVENTION
[0002] The invention relates to a push to communicate (PTx) or push
to talk (PTT) communication device or terminal, and particularly to
an audio data retransmission method in a PTx communication
network.
BACKGROUND
[0003] In general, a push to talk (PTT) terminal refers to a
terminal that allows real-time communication between two at least
two parties (e.g., from a transmitting party to a receiving party).
The transmitting party presses a certain key of a transmitting PTT
terminal before starting to speak. The transmitting PTT terminal
then transmits the respective audio data to one or more receiving
PTT terminals.
[0004] The transmitting PTT terminal will be able to receive audio
data or maintain a stand-by mode when the PTT key is not pressed.
The PTT terminal performs one-to-one or one-to-many communication,
and more particularly, operates in half-duplex mode. The PTT
terminal, typically, transmits audio data by grouping and
transmitting the audio data in packets over a CDMA or GSM network.
The corresponding audio data is transferred to a destination by
using VoIP (Voice Over Internet Protocol).
[0005] A user can input audio data through a microphone of the
transmitting PTT terminal when a PTT key is pressed. An inputted
audio signal is converted into a digital signal and an appropriate
transmission format prior to transmission.
[0006] A receiving PTT terminal receives and processes the digital
signal to reproduce the associated audio data through a speaker of
the receiving PTT terminal. If the receiving party does not receive
the transmitted audio data (i.e., the transmitted audio data is
lost) due to degradation of RF reception signal or the base
station's transmission inefficiencies, the receiving PTT terminal
requests from the transmitting PTT terminal to retransmit the lost
audio data.
[0007] In this case, the transmitting party will need to re-input
the audio data through the microphone to retransmit the lost audio
data. If the receiving party continuously fails to receive the
audio data, the transmitting party must inconveniently repeat the
above retransmission process over and over again.
[0008] A solution to the above problem is needed.
SUMMARY
[0009] In accordance with one aspect of the invention an audio data
retransmission method in a PTx (push to communicate) communication
network is provided. To achieve these and other advantages and in
accordance with the purpose of the invention, as embodied and
broadly described herein, a data retransmission method in a push to
communicate (PTx) communications network for transmitting data from
a transmitting PTx terminal to a receiving PTx terminal is
provided.
[0010] The method comprises transmitting first data from a
transmitting PTx terminal to a receiving PTx terminal; storing the
first data; and retransmitting the first data in response to the
receiving PTx terminal requesting retransmission of the first
data.
[0011] In one embodiment, the first data is stored in a buffer. The
buffer is implemented as at least one of an internal memory and an
external memory in the transmitting PTx terminal. The first data
may be outputted through a speaker in the retransmitting process
and deleted when a PTx key of the transmitting PTx terminal is
pressed to transmit second data. A PTx key is implemented on the
transmitting PTx terminal, such that interacting with the PTx key
results in transmission of the first data.
[0012] In accordance with another embodiment, an audio data
retransmission method in a push to communicate (PTx) terminal for
transmitting audio data comprises setting an automatic audio
retransmission function; storing audio data, to be transmitted to a
receiver PTx terminal, in a buffer; and retransmitting the audio
data stored in the buffer, in response to the receiver PTx terminal
requesting retransmission of the audio data.
[0013] In accordance with yet another embodiment, a mobile terminal
apparatus that supports a push to communicate (PTx) function is
provided. The apparatus comprises a radio frequency unit adapted to
communicate radio communication signals; a codec adapted to process
audio inputs provided by a user via a PTx function; a memory
adapted to store the processed audio inputs; and a microprocessor
unit adapted to control said codec to forward the processed audio
inputs to said memory for storage after the processed audio inputs
are transmitted to another user via said radio frequency unit, the
microprocessor unit further adapted to control said radio frequency
unit, said codec, and said memory to retransmit the processed audio
inputs stored in said memory, if said another user requests
retransmission of the processed audio inputs due to a loss in
transmission.
[0014] In a preferred embodiment, a communication network is
configured for supporting a push to communicate (PTx) communication
protocol, such that the communication network comprises a plurality
of base stations in communication with a plurality of PTx
terminals, wherein a transmitting PTx terminal requests a talk
burst grant from a PTx server for transmitting audio data to a
receiving PTx terminal, wherein the transmitting PTx terminal
stores the audio data in a storage medium when the request for talk
burst grant is submitted, so that if the receiving PTx terminal
fails to receive the audio data, the stored audio data is
retransmitted.
[0015] A data communication protocol for a push to communicate
(PTx) mobile communications network may comprise detecting a floor
grant for data communication between a transmitting PTx terminal
and a receiving PTx terminal; determining whether a failure has
occurred in transmitting first data to the receiving PTx terminal;
and notifying the transmitting PTx terminal of failure in data
transmission, wherein the transmitting PTx terminal retransmits the
first data in response to receiving a failure notice, and wherein
the first data is stored in a storage medium of the transmitting
PTx terminal.
[0016] The failure in transmitting the first data is determined,
when a threshold time has lapsed from time of the floor grant, or
when the transmitting PTx terminal does not receive an
acknowledgement of receipt from the receiving PTx terminal. In
alternative embodiments, a failure is determined when a receiving
PTx terminal receives data from a transmitting PTx terminal, but
the receiving PTx terminal can't hear or understand the data, due
to noise or other transmission problems. When a failure is
determined, the transmitting PTx terminal automatically retransmits
the first data, in certain embodiments.
[0017] In another embodiment, a push to communicate (PTx) terminal
comprises a transmitting unit for requesting a floor grant for data
communication between a transmitting PTx terminal and a receiving
PTx terminal; memory for storing the first data in a storage medium
of the transmitting PTx terminal; and a processing unit for
determining a communication failure, if a failure occurs in
transmitting first data to the receiving PTx terminal; wherein in
response to determining a communication failure, the transmitting
PTx terminal retransmits the first data.
[0018] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0020] FIG. 1 is a state diagram of data communicated in a push to
communicate (PTx) communication network, in accordance with one
embodiment of the invention.
[0021] FIG. 2 is a block diagram of a PTx terminal according to a
preferred embodiment.
[0022] FIG. 3 is a flow diagram of an exemplary method of operating
a PTx terminal for retransmitting lost data, in accordance with the
preferred embodiment.
[0023] FIG. 4 is a block diagram of an exemplary PTx terminal in
accordance with one embodiment.
[0024] FIG. 5 is a block diagram of an exemplary PTx communication
network in which the PTx terminal operates.
[0025] Features, elements, and aspects of the invention that are
referenced by the same numerals in different figures represent the
same, equivalent, or similar features, elements, or aspects in
accordance with one or more embodiments of the system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] A preferred embodiment is directed to a method for
retransmission of lost audio data in a push to communicate (PTx)
communication network. In a PTx communication network, a
transmitting communication device can single or multicast audio
data to one or more devices in the network. After a PTx key of a
PTx communication device is pressed, a user may input audio data.
The inputted audio data is temporarily stored, so that the stored
data can be retransmitted in case the first transmission is
unsuccessful.
[0027] Referring to FIG. 1, a PTx communication session may be
established between a transmitting PTx terminal and a receiving PTx
terminal over RTP (Real-time Transport Protocol). RTP is an IP
(internet protocol) that supports real-time transmission of voice
and video. RTP is widely used for IP telephony and audio and video
streaming. An RTP packet is transported on top of UDP (User
Datagram Protocol), and includes time stamping and synchronization
information in its header for proper reassembly at the receiving
end.
[0028] In accordance with one embodiment, a transmitting PTx
terminal submits a floor request (i.e., request for talk burst
authority) over the RTCP (Realtime Control Protocol). The request
is received by a PoC (push to talk over cellular) or PTx server
which can grant the floor request. If the request is granted, a
talk burst grant is transferred over the RTCP to the transmitting
PTx terminal.
[0029] In a preferred embodiment, the receiving PTx terminal is
also notified of the grant of the request and thus waits to receive
audio data from the transmitting PTx terminal. Once the
transmitting PTx terminal has the floor, the transmitting party may
input audio data (e.g., by way of speaking). The inputted audio
data is then transmitted over the RTP to the receiving PTx terminal
by way of the PoC server, for example.
[0030] If the transmitted audio data is not received by the
receiving PTx terminal after a threshold time has lapsed (e.g.,
data is lost), then the receiving PTx terminal transfers a failure
notification (e.g., NACK) to the transmitting PTx terminal over the
RTCP. Once the transmitting PTx terminal receives the failure
notification, the lost data is retransmitted as provided in further
detail below.
[0031] It should be noted that a fault in data transmission can be
detected in different manners. Thus, in alternative embodiments,
the failure in transmission or receipt of faulty data may be
detected by way of the receiving PTx terminal failing to send an
acknowledge (e.g., ACK) to the transmitting PTx terminal. In
alternative embodiments, a failure is determined when a receiving
PTx terminal receives data from a transmitting PTx terminal, but
the receiving PTx terminal can't hear or understand the data, due
to noise or other transmission problems.
[0032] Referring to FIG. 2, a PTx terminal according to a preferred
embodiment comprises a radio frequency (RF) unit 10, a MPU
(Microprocessor Unit) 11, a codec (Coder and Decoder) 2, a speaker,
a microphone and a buffer 13. The RF unit 10 is for performing
radio communications. The MPU 11 is for performing general control
operations.
[0033] The codec 12 is for converting an analog audio signal
inputted through a microphone into a digital audio signal which is
then provided to the MPU 11 for processing. In a reverse direction,
the codec 12 converts a digital audio signal received through the
MPU 11 into an analog audio signal for output through the
speaker.
[0034] The buffer 13 can be implemented as internal or external
memory. The buffer 13, in one embodiment, is connected to the codec
12 and provides for temporary storage of audio data, in case the
data is lost during transmission.
[0035] A dedicated user interface (e.g., a PTx key) may be provided
on the PTx terminal, so that a user can activate a PTx feature of
the PTx terminal by, for example, pressing a related key. In
alternative embodiments, this function may be activated by
selecting one of the keys provided on the keypad of the PTx
terminal or selecting from a graphic user interface menu displayed
on the PTx terminal's display screen.
[0036] Referring to FIG. 3, to activate an automatic retransmission
feature of the PTx terminal, a transmitting party may interact with
a transmitting terminal's user interface to activate the respective
retransmission Feature (S100). Once this feature is activated, the
transmitting party may press the PTx key to request talk burst
authority (i.e., to receive permission to transmit audio data from
a base station) (S200).
[0037] After pressing the PTx key, the transmitting party may input
audio data through the microphone of the PTx terminal (S300). The
inputted audio data is converted into a digital signal in the codec
12 (S400). The corresponding digital signal is stored in the buffer
13 (S500) and converted into a transmission format by the MPU 11
(S600) for RF transmission via the RF unit 10. The RF unit 10 then
transmits the data to a receiving PTx terminal (S700).
[0038] If the data is lost during the transmission (i.e., is not
received by the receiving PTx terminal) a request for
retransmission is submitted from the receiving PTx terminal to the
sending PTx terminal (S800).
[0039] The request for retransmission, in a preferred embodiment,
is automatically generated by the receiving PTx terminal. In an
alternative embodiment, the receiving party has the option of
manually requesting the lost data to be retransmitted (e.g., verbal
request, press of one or more buttons, select from a graphic menu,
etc.). When the transmitting PTx terminal receives the
retransmission request, it then retransmits the audio data stored
in the buffer 13 (S900).
[0040] In some embodiments, the retransmitted audio data is
reproduced via the transmitting terminal's speaker to enable the
transmitting party to listen to the audio so that he knows
retransmission is in process. In alternative embodiments, the
retransmission takes place silently.
[0041] In yet another embodiment, the retransmission may not take
place automatically. Instead, the transmitting party may be
notified of the failure of the initial transmission, by way of an
interactive message (e.g., audio alert, graphic alert, or a
combination of the two). In this embodiment, the transmitting party
will have the option of interacting with the transmitting terminal
to cause the stored audio data in the buffer 13 to be retransmitted
manually (e.g., by pressing a button for a predetermined length of
time or a predetermined sequence).
[0042] In is noteworthy that while the present disclosure is
directed by way of example to a PTx terminal and a PTx
communication network, the principals and features disclosed herein
may be applied to other types of communication devices or terminals
operating over a PTT, CDMA, TDMA, FDMA, WCDMA or GSM network, or
other functionally or structurally equivalent mobile communication
systems having one-to-one or one-to-many broadcasting features.
Further, in certain embodiments, instead of audio data other types
of data (e.g., video, text, multimedia) may be transmitted.
[0043] Referring to FIG. 4, a block diagram of an exemplary
embodiment of a PTx terminal 400 is illustrated. The PTx terminal
400 comprises a processing unit 410 such as a microprocessor or
digital signal processor, an RF module 435, a power management
module 406, an antenna 440, a battery 455, a display 415, a keypad
420, a storage unit 430 such as flash memory, ROM or SRAM, a
speaker 445 and a microphone 450.
[0044] A user enters instructional information (e.g., request for
talk burst, phone number, etc.) by pushing the buttons of a keypad
420 or by voice activation using the microphone 450. The processing
unit 410 receives and processes the instructional information to
perform the appropriate function, such as to dial the telephone
number. Operational data may be retrieved from the storage unit 430
to perform the function. Furthermore, the processing unit 410 may
display the instructional and operational information on the
display 415 for the user's reference and convenience.
[0045] The processing unit 410 issues instructional information to
the RF module 435 to initiate communication (e.g., transmit radio
signals comprising voice communication data). The RF module 435
comprises a receiver and a transmitter to receive and transmit
radio signals, respectively. The antenna 440 facilitates the
transmission and reception of radio signals. Upon receiving radio
signals, the RF module 435 may forward and convert the signals to
baseband frequency for processing by the processing unit 410. The
processed signals would be transformed into audible or readable
information outputted via the speaker 450, for example.
[0046] The processing unit 410 is adapted to store message history
data of messages received from and messages transmitted to other
users in the storage unit 430, receive a conditional request for
message history data input by the user, process the conditional
request to read message history data corresponding to the
conditional request from the storage unit, and output the message
history data to the display unit 415. The storage unit 430 is
adapted to store message history data of the received messages and
the transmitted messages.
[0047] FIG. 5 illustrates a block diagram of a PTx communication
network having a UTRAN 520 according to a preferred embodiment. The
UTRAN 520 comprises one or more radio network sub-systems (RNS)
525. Each RNS 525 comprises a radio network controller (RNC) 523
and a plurality of Node-Bs (base stations) 521 managed by the RNC.
The RNC 523 handles the assignment and management of radio
resources (e.g., authorizing talk burst requests) and operates as
an access point with respect to the core network. Furthermore, the
RNC 523 is adapted to perform the methods of the present
invention.
[0048] The Node-Bs 521 receive information sent by the physical
layer of the terminal 410 through an uplink, and transmit data to
the terminal through a downlink. The Node-Bs 521 operate as access
points, or as a transmitter and receiver, of the UTRAN 520 for the
terminal 410.
[0049] Although the present invention is described in the context
of a mobile communication device, the present invention may also be
used in any wired or wireless communication systems using mobile
devices, such as PDAs and laptop computers. Moreover, the use of
certain terms to describe the present invention should not limit
the scope of the present invention to certain type of wireless
communication system, such as UMTS. The present invention is also
applicable to other wireless communication systems using different
air interfaces and/or physical layers, for example, PTx, PTT, TDMA,
CDMA, FDMA, WCDMA, etc.
[0050] Preferred embodiments may be implemented as a method,
apparatus or article of manufacture using standard programming
and/or engineering techniques to produce software, firmware,
hardware, or any combination thereof. The term "article of
manufacture" as used herein refers to code or logic implemented in
hardware logic (e.g., an integrated circuit chip, Field
Programmable Gate Array (FPGA), Application Specific Integrated
Circuit (ASIC), etc.) or a computer readable medium (e.g., magnetic
storage medium, hard disk drives, floppy disks, tape, etc.),
optical storage (CD-ROMs, optical disks, etc.), volatile and
non-volatile memory devices (e.g., EEPROMs, ROMs, PROMs, RAMs,
DRAMs, SRAMs, firmware, programmable logic, etc.).
[0051] Code in the computer readable medium is accessed and
executed by a processor. The code in which preferred embodiments
are implemented may further be accessible through a transmission
media or from a file server over a network. In such cases, the
article of manufacture in which the code is implemented may
comprise a transmission media, such as a network transmission line,
wireless transmission media, signals propagating through space,
radio waves, infrared signals, etc. Of course, those skilled in the
art will recognize that many modifications may be made to this
configuration without departing from the scope of the present
invention, and that the article of manufacture may comprise any
information bearing medium known in the art.
[0052] The logic implementation shown in the figures described
specific operations as occurring in a particular order. In
alternative implementations, certain of the logic operations may be
performed in a different order, modified or removed and still
implement preferred embodiments of the present invention. Moreover,
steps may be added to the above described logic and still conform
to implementations of the invention.
[0053] As the present invention may be embodied in several forms
without departing from the spirit or essential characteristics
thereof, it should also be understood that the above-described
embodiments are not limited by any of the details of the foregoing
description, unless otherwise specified, but rather should be
construed broadly within its spirit and scope as defined in the
appended claims, and therefore all changes and modifications that
fall within the metes and bounds of the claims, or equivalence of
such metes and bounds are therefore intended to be embraced by the
appended claims.
* * * * *